Correlation of microdistortions with misfit volumes in High Entropy Alloys

The yield strengths of High Entropy Alloys have recently been correlated with measured or computed picometer-scale atomic distortions. Here, the root mean square microdistortion in a multicomponent alloy is shown to be nearly proportional to the misfit-volume parameter that enters into a predictive model of solute strengthening. Analysis of two model ternary alloy families, face-centered cubic Cr-Fe-Ni and body-centered cubic Nb-Mo-V, demonstrates the correlation over a wide composition space. The reported correlation of yield strength with microdistortion is thus a consequence of the correlation between microdistortion and misfit parameter and the derived dependence of yield strength on the misfit parameter. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.